Automatic door-engine control



Jan. 8, 1929; V

G. E. OAKLEY AUTOMATIC DOOR ENGINE CONTROL Filed March 17. 1927 INVENTOR scones E. OAKLEY BY lafdmz} ATTORNEY lPatented Jan. 8, 1929.

UNITED STATES PATEN Tf OFFICE.

GEORGE E. OAKLEY, OF ALBANY, NEW YORK, ASSIGNOR, BY MESN E ASSIGNMENTS, TO

CONSOLIDATED CAR-HEATING COMPANY, INC., OF ALBANY, NEW YORK, A COR- PORATION 'OF EW YOR AUTOMATIC DOOR-ENGINE CONTROL.

Application filed March 17, 1927. Serial No. i176,2%3.

For a detailed description of the present form of my invention,- reference may be had to the following specification and to the accompanying drawing forming a part thereof.

It has heretofore been proposed, in pneumatic door-operating systems for'car doors, that, upon the application of emergency airpressure to the brakes for stopping the car, there should be a simultaneous release of the car doors, which are being held closed by the pneumatic door engines, so that in an emergency the doors may be opened by hand with out need of waiting for the motorman to open them in the normal way by means of the door engines. For instance, if the motorman should become unconscious for any reason and let go his hold on the car-controlling mechanism the motor would be automatically shut off and the brakes applied by devices which are Well known; but it is also important that the car doors should at the same time be automatically set free for opening by hand so that the passengers will not be left imprisoned in the vehicle. Heretofore such automatic release of the doors has been provided for by causing air pressure to be admitted to the door-opening cylinder of the engine to counterbalance and neutralize the then existing pressure on the door-closing cylinder and thereby set the door free to be operated by hand. The objection to this method is that, if the closing cylinder should be leaking, which is a more or less frequent condition, the admission of air pressure to the non-leaking door-opening cylinder will overbalance the closing effect and positively open the door which is undesirable. My inventi on resides in. certain apparatus by which the presence of air pressure in the emergency brake-applying system acts to automatically remove pressure from the door-closing cylinder of a door engine, thereby releasing the door for manual operation without danger of actually opening the door.

Referring to the drawing, A represents an air pipe for delivering emergency air-pressureto the brake-applying agencies B B. It will be understood that, by known means indicated at T the service pressure as distinguished from the emergency pressure will reach BB by a different route. From pipe A a. branch pipe 0 leads to my differential control-valve which comprises a larger cylinder D with its larger piston O and, in

opposition thereto, asmaller cylinder D and its smaller. piston 0 the two pistons being rigidly connected. The aforesaid pipe C leads to the rear end of cylinder D and the rear end of cylinder D is permanently connected to the pressure reservoir E. In cylinder D is a port R across which travels the piston O and which is connected by pipe F to the intake of the door-control valve G that admits the air arriving from pipe F to either the door-closing cylinder H or the door-opening cylinder K of the door engine, while opening the other cylinder the drawing this valve G is shown in the position it would normally occupy when the car 1s running, viz, in the position to hold air pressure on the door-closing cylinder H,

to the exhaust S. In

while openingthe door-opening cylinder K larger piston Q and overcome the permanent pressure on the smaller piston 0 and force it to the right across the port R. Until this occurs the pressure from, reservoir E is, not only holding piston O to the left of port R, but is also passing through that port to pipe and thence by valve G to the door-closing cylinder H of the engine. Manifestly the aforesaid shift of piston 0 will cut off the pressure from pipe F'and cylinder H and open them to the exhaust P, leaving the door engine with air on neither cylinder and the door free to be operated by hand. At times other than the supposed emergency the air supply for the door engine will come from reservoir E by way of cylinder D and pipe F to the engine control valve G. I make no claim herein to the car brake apparatus on which my device is applied, but what I do claim is:

' 1. The combination with the door-closing cylinder ofa car-door engine of an exhaust pipe therefor automatically opened by emergency pressure on the car brakes. I

2. The combination with a car-door engine of a control valve for exhausting the dooropening and door-closing cylinders alternately and a second exhaust for the doorclosing cylinder controlled by the brake pressure.

and its control valve, of an air supply pipe,

3. The combination with a car-door engine 4. The method of neutralizing the holding force of a car-door engine in an emergency which consists m applying emergency pressure on the car brakes and causmg said emergency pressure to effect the connection of both the door-closing and the door-opening cylinders to the atmosphere at the same time.

5. An air-brake system comprising a manual brake controlling valve, an electrically operated valve controlling both the brake and the door-engine, and an automatic means for controlling the said electrically operated valve from the manual valve.

6. An air-brake system comprising a manual brake-controlling valve, an electrically operated valve controlling both the brake and the door-engine, and automatic means for controlling the said electrically operated valve includin by the manual y admitted air pressure and the other by the operators grasp of the steering valve for the vehicle.

Signed at Albany, county of Albany, State of New York, this 11th day of March, 1927.

GEORGE E. OAKLEY.

two switches, one operated 

